Safety device fob hydbaclic brake



Oct. 3, 1939. s. c. GEORGE Er AL R- 21,223

SAFETY DEVICE FOR HYDRAULIC BRAKE SYSTEMS Original Filed F'eb. 16, 1937 2 Sheets-Sheet 1 In venters 20023@ rjfJ-.Wza M By @am w13@ Oct. 3, 1939. s. c. GEORGE Er AL ZRe. 21,223

SAFETY DEVICE FORVHYDRAULIC BRAKE SYSTEMS Original Filed Feb. 16, 1937 2 Sheets-Sheet 2 Inventors 6i 3 @gygy ZfJ/Lfer forneys Rented/'0a. 3,1939

'rv ori-lcs SAFETY DEVICE FOB HYDRAULIC BRAKE SYSTEMS Simon C. George, Greensburg, and John J. Weber.

Pittsburgh, Pa.; said Jo Edna C. Weber, Pittsburgh, Pa.

hnlweberasaign'crte origins: No. 2.127.399, wea Amst 1s, im, se-

'ihll No. 126,052,

February 1 9, 1937.

A A ction for reissue June 30, 1939, Serial No. w3

4 claims. `(ci. :os-w

This invention relates broadly to hydraulic brake systems for automobiles and more particularly to a device for use in conjunction with such systems as a safety measure.

In accordance with the present invention means is provided in a hydraulic brake system whereby in the event of the breakage or occurrence of a leak in the iluid line leading to either the front or rear wheel brakes the iiow of fluid 10 through the leaking line will be automatically arrested while at the same time the fluid may flow through the unaffected line for applying the wheel brakes associated with said liine.

A further object of the invention is to provide 15 a device of this character which may be used f with equal facility in the air brake system of commercial vehicles.

A still further object of the invention is to provide a device of this character which is free of springs, etc., which might break or otherwise get out of order thereby rendering the device ineffective for the purpose intended.

'I'he invention together with its objects and advantages will be best understood from a study of 25 the following description taken in connection with the accompanying drawings wherein:

Figure 1 is a plan view illustrating the application of the invention to a hydraulic vehicular brake system.

Figure 2 is an enlarged sectional the safety device.

Figure 3 is a transverse sectional view taken substantially on the line 3 4 of Figure 2.

Figure 4 is a fragmentary detail sectional view 35 showing the position of one of the hollow plungers when a break occurs in the line connected with the cylinder in which said plunger operates.

Figure 5 is a view somewhat similar to Figure 4 and illustrating the use oi' the adjusting screw lo for bleeding the safety device.

Figure 6 is a perspective view of a key hereinafter more fully referred to.

Referring to the drawings by reference numerals it will be seen that the numerals 5 5 indicate L5 the brakes associated with the front wheels of an automobile while the numerals 6 9 indicate the brakes mociated with the rear wheels of a vehicle. The fluid feed line for the brakes I is indicated by the reference numeral 'I while the iiuid D feed line for the wheel brake 9 is indicated by the reference numeral 8. The master cylinder assemblyv of the hydraulic brake system is indicated generally by the reference numeral 9 and the brake pedal connected with the master pis- 5 ton is indicated by the reference numeral I9.

Our improved safety device is indicated generally by the reference numeral II.

30 view through As clearly shown in Figures 2 to 6, inclusive the improved safety device II comprises a block or casting I2 suitably bored to provide a.pair\of cylinders Il and Il respectively, open at one end and at said open end being closed by a plate indicated by the reference numeral II. The cover plate Il is secured to the block or casting Il through the medium of screws or other suitable fastening elements I'I.

Between the cylinders i3 and Il the casting or body block I2 at one end is provided with an inlet passage Il that is suitably connected as at I 9 with the outlet of the master cylinder 9.

Also for the cylinders Il and I 4 there are provided at the inner ends of the passage I8 lateral ports 29, 2| respectively while at the end thereof remote from the ports 2l, 2| the body block or casting l2 is suitably bored to provide for the cylinder It lateral ports 22, 23 connected by a passage 24: and to provide lateral ports 25, 2G for the cylinder Il and al passage 2l connecting the ports 2l and 2l.

The cylinder Il is connected with the fluid conduit 'I for the front wheel brakes 5 while the cylinder Il is connected with the conduit l for the rear wheel brakes l.

Having a sliding fit within the respective cylinders Il and Il are holiowsliding valve members 28 and 29 respectively. The valve members 28, 29 are open at one end and at said one end are internally threaded for the reception oi' plugs 3l. v

For retaining the membersI 2l, 29 against rotative movement within the respective cylinders I3 and Il the plugs I9 are provided with kerfs or ways II which receive the bevelled edges of keys 32 that are also engaged in grooves 33 provided therefor on the inner face of the cover plate I 5 as clearly shown in Figure 2.

The valve members 28A, 29 at one end are respectively provided with lateral ports 94, 35 respectively for registry with the ports 2li, 2i. Adjacent the other end thereof the respective valve members 2l, 2l are provided respectively with lateral ports 96, 31, the port Il of the valve member 2l registering with the port 22 when ports 34 and 20 are in registry. Similarly the port 31 of the valve member 29 is in registry with the port 25 when ports 2i and 35 are in registry, and is out of registry with port 25 when ports 2i and Il are out of regist From the foregoing it willbe seen that normally the valves 2l and 29 are in the position shown in Figure 2 so that when the brake pedal III is depressed for applying the wheel brakes fluid from the master cylinder 9 ows through the valve members 28 and 29 to the lin l and l occur in the line l it released under valve 20 causing' and through and i for applying ously. Assuming, for example, that a leak should will be seen that immedithe said brakes simultaneventing further loss of iiuid. At the same time the valve member I8 would remain in the posian invention of this character will respective conduits,

tion shown in Figure 2 so that the fluid from the master cylinder would pass through the e It aligned ports 2l and u' into the valve 28 and from the valve 2l through the ports Il and 22, flowing through the passage 24 to return to the cylinder il through the port 2l then passing from the cylinder I3 through the line 1 to the vehicle brakes l. l

suitable means,'such as vent openings Il, may be provided in theplate Il or in the end of the casting provided with the inlet pipe il, to prevent the creation of a vacuum in the adjacent ends of the cylinders during the movement of the valve therein into its position for cutting of! the iiuid from the master cylinder. From this description of the operation of the device the manner in which the device will operate in the event of breakage in the line 1 is thought to be obvious.

For resetting a valve member 2l and Il as the case may be, after the repair to the broken line has been made, or for bleeding the brakes in the usual manner for servicing the device recourse is had to the proper adjusting screw 3l there being provided one adjusting screw Il for each cylinder, the screw being threaded through the end wall of the cylinder remote irom the cover plate Il and provided with a lock nut I9. In servicing the device by bleeding the brakes the selected screw I8 is threaded inwardly to the position shown'in Figure 5 to engage the adjacent end of the associated valvev 28 or 2l either to hold the valve in position shown in Figure 5 or to shift the valve from the position shown in Figure 4 to the position shown in Figure 5 whereby the iiuid may iiow from the valve 2l or 29, as the case may be, through the ports 8l, 22, passage and port 23 back into the cylinder il in the case of valve 2B, and through the portsj'l, 25, passage 21 and port 26 in the case of the valve It.

It is thought that of the construction,

a complete understanding utility and advantages of be had without a more detailed description.

What is claimed is:

1. In a hydraulic brake systemfor vehicle, the combination with the'front and rear vehicular wheel brakes, a master cylinder, a conduit for supplying fluid from the master cylinder to the front wheel brakes-and a conduit for supplying cylinder to the rear wheel brakes, of a device interposed between the master cylinder and said conduits and providing a connection between the said device includingindecylinder to the line l this prerespective cyllnd relatively opposite end being through the valve members,

master cylinder and the amas tneuneenndltetnebrekeel pendently operable hollow valve means for' each conduit and through which the :duid ports in the valves communicating with the conduits, said valves being slidably operable to cut of the the ports in the event of leakage in the conduit without retardlng the ilo of iiuid thro'ugh the unaffected conduit.

2. In a hydraulic brake system for vehicles, the

combination with the front and rear vehicular wheel brakes, a master cylinder, a conduit for supplying ilid from the master cylinder to the front wheel brakes. and a conduit lor supplying iiuid from the master cylinder to the rear wheel brakes, of a. devi interposed between the masterfcylinder and said conduits and providing a connection between the master cylinder'and the respective eonduite. seid device ineliding e peu of cylinders, one for each valve members ving asliding ilt within the and normally maintained in ure of the fluid in said conone position by p eduits, said cylinders and valves having registrable ports providing communicating\.through the valve with the respective conduits and said valves beingoperable to shift to a second position for cutting oi! the flow of fluid to an affected conduit when the pressure is reduced in said affected conduit.

3. A safety device for hydraulic brake apparatus and the likeprovided with a bore constituting a cylinder having a lateral intake port at one end and at a relatively opposite end being provided with a pairof relatively spaced lateral ports and a e connecting said ports, and a hollow cylindrical valve member having a sliding t within said cylinder and movable with the hydraulic iiuid feeding through the brake ap' paratus and said valve in the event of breakage in a conduit of the brake apparatus, said hollow valve member being provided adjacent one end thereof with a lateral port normally registering withthe ilrst mentioned lateral port of the cylinder and said valve member adjacent its provided with a lateral port normally registering with one of said pair of ports to provide for a free now of fluid through the cylinder and said valve memberA under normal working conditions.

4. In a hydraulic brake system `for vehicles, the combination with the front and rear vehicular wheel brakes, a master cylinder, a conduit for supplying iluid from the master cylinder to the front wheel brakes, and a conduit for supplying iiuid from the master cylinder to the rear. wheel brakes, of a device interposed between the master cylinder and said conduits and providing a connection between the master cylinder and the respective conduits, said deviceincluding a pair of cylinders, one for each conduit, and hollow valve members having a sliding iit within the respective cylinders and normally remaining in one position to provide for a free flow' of iluid and also being operable to shift to a second position for cutting oir the ilow of uid to an eilected conduit, and an adjusting screw threaded in one end of each of said cylinders to engage an end of the valve member therein for moving the valve member to one position' of adjustment and holding said valve member in said position of adjustment, as

'and for the purpose specified.

SIMON c. GEORGE. JomLJ. WEBER.

conduit, and hollow 

